![]() ![]() Also, we optimised in 2016 a four-stage procedure for fat in olive fruits using 100 mL of solvent for 2.5 h. We validated in 2005 a five-stage analytical procedure for PAHs in airborne particles using the NIST 1649a (National Institute of Standard and Technology, Gaithersburg, MD, USA) where extraction was performed by Soxhlet with 250 mL of solvent for 10 h. Optimisation of the new procedure: extraction, purification and quantification The relevance of the work is the fact that many modern techniques that reduce solvent volume and time consumption are costly when there is currently a global crisis due to SARS-CoV-2.Īll solvents used in the present study were of analytical and chromatographic grade. This spiking technique constituted an innovative idea in validation techniques. Additionally, the reference material was mixed with small pieces of unexposed filter, taking the mixture as a new reference for the same matrix of real samples of particles, which are collected on filters during the sampling. Regarding the validation process, suitable certified reference materials should be used, but it is much better with two references to confirm the suitability of the method. The method was based on an improved and more rapid Soxhlet extraction plus an improved, short and more efficient SPE technique for the 16 PAHs included in the US EPA priority pollutant list in airborne particles. Therefore, the aim of this paper is to optimise and validate a low-cost and rapid extraction methodology with low time and solvent consumption. Additionally, after extraction step, it needed purification steps by solid-phase extraction techniques like packed columns of silica, Florisil®, alumina or mixtures. An improved Soxhlet technique, called hot Soxhlet, heats the extractor body at lower temperature than the boiling point of solvents to keep it in the liquid state. Soxhlet extraction represents an inexpensive method for solid samples, nevertheless is rather time-consuming and requires high solvent consumption. However, these new techniques are expensive. In order to speed up sample preparation, new methodologies such as accelerated solvent extraction or microwave-assisted solvent extraction or ultrasound-assisted solvent extraction have been developed, saving processing time and solvent consumption. Traditional extraction procedures for PAHs involve many techniques, such as direct extraction with organic solvents, sonication and Soxhlet extraction. Determination of low levels of PAHs in complex matrices such as atmospheric particles leads to a search for accurate analytical methodologies, which need to be optimised and validated with recognized material references. In the atmospheric environment, PAH emissions are well known, as they originated from car exhausts, domestic combustion, industrial activities, agriculture activities and natural sources, such as biomass burning. Similar measures were taken by other European organizations. ![]() ![]() The European Commission exposed a wide toxicological guidance since the 2001 position paper to the Europe 2020 strategy. These hazardous hydrophobic organic compounds (HOCs) led international organisations to establish policies for the environment and indoor air. Polycyclic aromatic hydrocarbons (PAHs) are lipophilic compounds with important carcinogenic risk. ![]()
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